Caisson head



Nov. 4, 1930. F.,B. csoLDslsoRouGr-xV CAISSON HEAD Filed Nov. 13, @25

l INVENTOR '"7 2' a MW f BY A TT ORNE YS Patented Nov. 4, 1930 UNITED. STATES FREDERIC '.B. eoLDsBoRoUeH, or caoron-onnunsonnnw YORK CAISSON 'HEADv `Application filed November Heretofore, caissons have been provided f with air-lock heads` and also with means,

such as buckets, fory hoisting the excavated material, but these havebeen unsatisfactory y when attempted to be operated together due to the 'cumbersome apparatus andthe unreliability of'its operation. For example, one method, which requires the services of three or more men, employs an airflock caisson head having the customary outlet chamber n and which is provided with a'pulley over 15 which passes the hoisting cable to an engine v usually on the ground at a distance from the caisson. Consequentlywhen a loaded bucket is drawn upwardly, the unbalanced sideward pull of the cable causes the caisson head to be subjected to a considerable stress which often causes'it to bend and rock as the bucket is raisedand lowered. The sideward pull also causes the caisson to deflect somewhat fromits intended path as it goes down, un-l less means arevused to counteract this tendency,v `Moreover such an arrangement occupies considerable space land the scattered apt paratus usually interferes with'otherv concurrent operations.

off thedrum'at rightfangles to its-axis.

With such an arrangement the length of ,c the hoisting cable between the engine and the l bucket .continually changes as the caisson goes into the earth, so .that the distance through vwhich the bucket is raised or loweredmust bek carefully gauged'by the oper- ,v ator" of the enginev tov prevent the bucket p n The hoisting engine '30 must be properly set with respect to thecable in orderl that lthe latterrmay be' run .on andV 13, 1925. seriai m1468317."

andthe engine orv upon their skill and-judgment in manipulating the apparatus;

The principalobj ect of the invention is to provide a caisson head having all ofthe necessary operatingapparatus in a unitary self-containedstructure. Y f

`By virtue of this arrangement lthe entire caisson emplacement apparatus occupies no more superficial area than thecaisson proper and requires nol external auxiliary ap` paratus whatever, so that the danger of deiiecting the caisson as it sinksris avoided as welll as other disadvantages attending the use of such external apparatus. Since the distance between the hoisting apparatus and.-G5 the'bottom of the caisson isl constant the hoisting cable maybe suitably markedutoy show when the. apparatus should be started or stopped, or automatic means may beemployed .for giving signals or even for controlling the operation of the apparatus.

The particular nature of the inventionas well as other objects and advantages there-4 of will appear mostvclearly from a description ofV the preferred embodiment tl'iereof illustrated in they accompanying drawings, in which'like reference characters denote ylike parts .in the several views, i

Figure l is an external view of an em- Vplaced caisson utilizing the caisson head' disclosed by this invention, and l Fig. 2 is a vertical section of the' caissonhead along the line 2 2 of F ig. l. Y

Referring to thefdrawings letter A designates the caisson incwhich excavating is being done under air pressure, andletter B de-V notes the entire caisson head whichY is mounted on the caisson A by meansofre-` movable bolts 1, whereby the caisson head Bis attachedto and maybe llikewise re- Q0 moved from the Caisson A. y The air-lock of caisson head Bis of Vthe conventional type well known in theart'and consists inbrief of the built-up steel cylindri-` cal shell 2 which is slightly larger in diameter than caisson A, and having a transverse diaphragm 3 provided with an openingk which is closed by the ydownward swinging lock door 4, hinged at one edge and held in closed position by the counter Weight 5 which must be thrown Vline 9 passes into the lock chamber of cassion head B and also into the chamber of caisson A. rEhe top 10 of caisson head B is provided with a cable blockll through which the hoisting cable 12 passes. rIhe caisson head B is provided with oint packing where necessary so as to make it practically hermetically sealed.

In accordance with this invention, a winch is mounted on the top 10 of caisson head B, and which may be either power operated or hand operated as desired, and in the drawings the winch is shown to be power operated for the purposes of illustration. The cable 12 passes through cable block 11 and over pulley 13 which is mounted in a swivel support 14 so as to turn as the cable 12 is wound along win linO' drum 15, which` may be moved along its axle 1G by means lof a lead screw for example,

soasto wind the cable evenly upon the drumv 15, or by any other manner of winding commonly resorted to.

` An electric motor 17 may be used for driving the drum and which, for purposes of convenience, mayl be continuously running and .coupled to and uncoupled from the drum 15 by means of lever 18 which operates clutch disposed in housing 19. j Another lever 20 operates reversing gearing, also disposed in housing'19, whereby the rotation of winding drum 15 may be reversed as the bucket 21 is raised and lowered. rIhe entire winch, comprising motor 17, winding drum 15, and clutch and gear housing 19, may be mounted upon one bed plate 22 which is in turn mounted rigidly to the top 10 of caisson head B. y

Inasmuch as the type of caisson head illustrated in the drawings is usually of alarge size, a scaffold or platform, not shown in the drawings, is erected around the caisson head B, whereby the operating parts'thereof become more readily accessible to the operator.

Having described the structure of the caisson head of this invention, the operation thereof will now be explained. Assuming that the excavator in the pit of the caisson A has filled the bucket 21, he gives a hoisting signal, usually by rapping the side of the caisson or by other signalling means, whereupon the winch operator throws the clutch into engagement by means of clutch lever 18, which revolves the winding drum 13 to hoist f the bucket 21. Nhen the bucket 21 has passed through the lock at door 4, as is visible to the winch operator through glass ports 23 in the wall 2 ofthe caisson head, the clutch is disengaged by means of lever 18, lock doo-r 4 is closed by throwing the counterweight 5 to the position opposite that shown in Fig. 2, door 6 is slid open, and bucket 21 removed for dumping. When discharge door 6 is opened the trapped air rushes out, but the caisson A is closed by lock door 4 and thus a practically constant air pressure is maintained therein.

Having emptied the bucket 21, it is replaced in thecaisson head chamber, door 6 is closed whereupon the caisson head chamber fills with compressed air from line 9, gear lever 2O is moved to shift gears to reverse the direction of rotation of winding drum 15, counterweight 5 is thrown over to the position shown in Fig. 2 Vto open lock door 4, the winch clutch is thrown into engagement by means of lever 18 which lowers the bucket 21 into casion A, and the winch clutch is disengaged when the bucket 21 reaches the pit of the caisson.

r.The workman who does the excavating is lowered into the 'pit of the caisson in the same manner i. e., he steps into the air lock chamber, door G is closed after him and the air turned on gradually and slowly so that his body may adjust itself to the increased external pressure. Vhen the requisite working air pressure is attained he is lowered into the caisson pit through the opening at lock door 4. In emerging from the caisson the above described operation is reversed and the workman is subjected to a gradually and slowly decreasing air pressure down to approximately normal atmospheric pressure before he is allowed to come out of the caisson head. These precautionary measures are necessary because of the disagreeable physical consequences attending the subj ection of a person to sudden and considerableincreases or decreases in air pressure.

lVhile this specification and the accompanying drawings disclose a specific structure and arrangement of parts, it is to be understood that such disclosure is only employed for the purposes of illustration and that changes may be freely made in the structure and arrangement of parts without departing from the spirit of the invention within the scope of the appended claims. For instance, on account of the constant distance between the winch and the pit of the casing any suitable mechanism for automatically controlling the starting and stopping of vthe winch may be employed, but as mechanisms for this purpose are well known, none has been illustrated.

I claim: l

V1. In a hoisting and air-lock apparatus for caissons, the combination with a caisson of an air-lock head joined thereto, a door controlling communication between said caisson and said head, a hoisting means mounted on said head, a cable operable by said hoisting means passing through said head and into said caisson and a carrier suspended from said cable.

2. A hoisting and air lock apparatus for caissons comprising' a detachable caisson 'mounted on the `exterior thereof, va flexible charge door in the side of said chamber above 'i said vlirst named door, a hoisting winch atop ysaid chamber, a cable adapted to pass through the doorway of said firstsnameddoor and operable by said winch, and a carrier attached to said cable.

4. In a hoisting and air-lock apparatus for caissons, the combination of a caisson sha-tt,A `a detachable airelock head attached thereto, a hoisting winch mounted on and exteriorly` of said head, and hoisting means operable by said winch passing through'said air-lock and into said shaft.

'5. A caisson headv comprising the unitaryy combination of a caisson air-lock and a winch element controlled by the winch entering said air-lock and a'carrier secured thereto, whereby material may be hoisted from a caisson into the air-look and vice-versa.

6. A- caisson head comprising a cylinder closed atthe top and having a trap door at the bottom, a winch mounted atop said cylinder, a cablepassing from the winch through the top of the cylinder and through the doorway 'for said door and operable by said winch, a. bucket on said cable, and a door in 'the side of said cylinder whereby material is discharged after having been hoisted through said lirst named door and into said cylinder.

7. In a head for receiving and discharging materials for caissons, the combination of a shell forming the body thereof, of a trapdoor in the bottom of said shell, of a winch mounted on the top ofsaid shell, and of a bucket and cable operable by said winch and passing through said trap-door.

I-n testimony whereof I aiiiX my signature.

FREDERIC B. GOLDSBOROUGH. 

